Telephone system.



F. M. SLOUGH.-

TELEPHONE SYSTEM- APPLiCATION man JULY 26. m5.

Patented Apr 9, 1918.

PATENT @Fldltll j,

FRANK M. snooen, or ELYBIn,

OEIO, ASSIGNGR, BY MESNE ASSIGNMENTS, T0

STBOMBERG-CARLSGN TELEPHONE MFG. CO., OF ROCHESTER, NEVJ YORK, A COR- PORATION OF NEW YORK.

TELEPHONE SYSTEM.

Application filed July 28, 1915.

To all whom it may concern:

Be it known that I, FRANK M. SLOUGH, a citizen of the United States, residing at Elyria, in the county of Lorain and State of Qhio, have invented certain new and useful improvements in Telephone Systems; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

My invention relates to telephone systems and to improvements therein, for the purposes of performing certain useful functions in attaining useful objects which will be apparent from a description of an embodiment of the invention, such as shown in the accompanying drawing.

One of the objects of my invention is to provide means whereby an electrical potential suitable for causing a busy test is placed upon the terminals of a line when the subscriber comes in upon the line, without causing any disturbance in the apparatus of the subscriber.

Another object of my invention is to provide means controlled by the subscriberupon making a recall for disconnecting the telephone interconnecting means, so as to release the line for a new call.

These and other objects of my invention will probably be better understood from a description of an embodiment of the invention.

The drawing shows diagrammatically a telephone system embodying my invention.

Referring now to the embodiment illustrated. in the drawing, at I is shown a telephone line which leads from a substation shown at A to a main station shown at 11. Although but two substations are shown upon the line I, it is obvious that any number may be connected thereto. For the purpose of this description, this line will be spoken of as the calling line, it being assumed that the calls, whose operation will be described, are initiated by the subscriber at A. At 111 is shown a second telephone line leading from a plural ty of substations, one of which is shown at B, to the main station. The line 111 will be spoken of as the called line. The main station shown at H is equipped with operators telephone line Specification of Letters Patent.

Patented Apr, 9, 11.5218.

Serial No. 41,839.

interconnecting apparatus, here shown as a cord circuit C, which includes a pair of talking strands 1 and 2 and a third strand 3. An operators telephone set is shown at O and a source of ringing current is shown at It.

The interconnecting means employed in the embodiment of my invention illustrated is shown as a cord circuit C. Switches are provided for connecting the cord circuit to telephone lines, here shown as a switch D, which will hereinafter be spoken of as the answering switch, and a switch E which will hereinafter be spoken of as the calling switch. in the embodiment of my invention shown, these switches consist of plugs and jacks, the lines terminating in multiple acks which cooperate with the plugs P and P in which the strands of the cord circuit terminate for the purpose of making the connections. he multiple jacks of the line I are shown at J and j, and the multiple jacks of the line HI are shown at J, and 7' These jacks consist of a plurality of terminal contacts, some of which, here spoken of as ring contacts, are shown at 4: and 4,.

Assum ng that the subscriber at A desires to talk with the subscriber at B, the line relay is actuated, which closes a circuit including the line lamps X and 00, which indicates to the operator at station 11 that the subscriber at A desires a call. The actua' tion of the relay F also loses a circuit through the diiferential windings of the magnet of the relay G, placing an electrical potential upon the terminals land al so that any operator testing the line I after the subscriber comes upon the same, will receive a busy test, indicating that the line is busy and preventing the interruption or interference with the call initiated by the subscriber A. T he windings of the magnet relay G being differential, this relay will not be actuated at this time. One of the operators observing the illumination of one of the line lamps of the line I will answer the same by inserting a plug into one of the jacks of said line. Assuming that the operator controlling the cord G operates the switch D by inserting the plug P into the jack J, a circuit will be completed for the relays G and L through the contacts of the relay L The relay K will also be energized over the talking strands otthe cord and the line T.- The relay K will complete a circuit for the magnets of the relays L and G through the conductor 5 independently o1 the contacts of the relay L When the relay L was energized, a circuit was completed for the relay T, which operated, connecting the operators set to the cord circuit and placing her in communication'with the subscriber at A. The operator having learned that it is the subscriber at B that. is wanted, tests the line III; and assuming that it is found idle, operates the switching device the plug P into the jack J thereby completing circuits-tor the magnets G, and L The cut-oil relay G, acts in a well known manner to disconnect the line relay F and the line lamps X and 00 from the line Ill. The magnet of relay L interrupts the circuit of the relay T, thereby causing the disconnection of the operators set from the cord :circuit. This relay also closes contacts in the circuit of the supervisory lamp N, which is now lighted. The operator then depresses the ringing key S, connecting the ringing generator to the line Ill, for the purposeof calling the subscriber at B. The subscriber at B hearing this signal responds, causing the actuation of the relay K which interrupts the circuit of the supervisory lamp N, which-is now extinguished. The subscribers are now connected together over thelines and through the talking strands ofthe cord circuit. They converse, and at the termination of the conversation, the retirement of their sets interrupts the circuits of the relays l and K which become deenergized, whereupon the lamp N is lighted, indicating to the operator the retirement of the subscriber at B. The lamp Uwill also be lighted, indicating to the operator the tirement of the subscriber at A.

It frequently happens in the operation or' telephone systems that the operator is busy and does not immediately take down the disconnections, and in the old systems, the subscriber at A is unable to secure a recall at once, because he'is unable to control the line lamps of his line. However, in. the embodiment illustrated the interruption of the circuit of the relay K, when the subscriber at A retired, caused the opening of the conductor 5 and the breaking of the circuit through the relays G and Ti, thereby releasing the line lamps and line relay F of theline 1.

Assuming now that the subscriber at A. desires a recall, or to initiate a call before the cord, is disconnected from the line I, the subscriber can close the line and thereby a circuit for the relay F, which is actuated, causing the opera ion of the line lamp before,,and in addition, completing a circuit through the disconnect relay H, which E by inserting is actuated, iuterru sting the talking strands of the cord circuit and completing a locking circuit for itself, thereby making it possible for the operator controlling C, or any other operator, to answer the recall. This may be done'by the operator who controls the cord circuit C by closing the switch D A. detailed description of the operation of the embodiment of my invention illustrated in the drawings is as follows: The subscriber at A, removes the receiver 6 from the receiver hook 7, which being spring pressed upward, rises and closes the hook switchS,v

ings of G, however, are differential and will not cause the actuation of the contacts controlled thereby under these conditions. However, the contacts 4 and 4 will be energized, so that line after the switch 8' is closed, the line will test busy, in order to avoid another operator interfering with the call initiated by the subscriber at A, which sometimes happens in the systems used at present,

causing considerable contusion, owing to two or more operators connecting with the line A at the same time. In the system of when such test is made.

Assuming that the operator controlling the cord C answers the call, by employing the cord C, the switch D is operated in the embodiment shown, by inserting the plug P contact 20, sleeve contact 22 of the making electrical into the jack J, the tip contact 21 and the ring plug T registering and contact respectively with the tip spring 23, the sleeve spring 2' and the ring at of the jack. By the c a of the switch 1) a circuit is complctec for the magnets of the relays G and L, as follows: ground 15- winding 25 of the magnet of relay G-conductor 26l22conductor f28conductor 29winding of Lthe resist ance device li lbattery 30to ground at- 31;

Current flowing through this circuit will. pause the actuations of the magnets G and iJ. of the switches 10 and 14, and the disconnection ot the line relay and line lamps from the line 1, thereby removing the control of the same from the subscriber, whichwill enif a test is made upon this 27'switch" The actuation of G causes the opening my invention, no disturbance is caused: at A dure as long as the relay G is energized. The energization of the magnet of the relay Lrcloses a switch 32, shunting the device M, whereby the call is captured by the operator controlling the cord C in a manner well understood, and which constitutes no part of my invention. The magnet of the relay L also closes the switches 33 and 34, placing the relay K across the cord circuit. A circuit is now completed for the relay K, as follows: from battery 35through winding36 of Kconductor 37I202313- 78121l2 l21--2-i0switch winding 41-back to battery. The magnet of the relay K will be actuated closing a switch 42 in the conductor 5, and thereby completing a new circuit for the relays L and G, which is as follows: ground 31- battery 3032L-42-5conductor A3 27-22-42625back to ground at 15. The magnet K also opens a switch 44 in the circuit of the relay H, for a purpose to be described. The magnet L also opens a switch 45 in the circuit of the relay H, for a purpose to be described and closes a switch 46 in the circuit of the magnet of T, which circuit will be completed, as follows: 3l-46conductor A7-magnet of Tconductor 48switch 49battery 50to ground 51. The magnet of T will be energized, closing the switches 52 and 53, and connecting the operators set 0 in circuit with the subscribers set at A, whereby the operator communicates with the subscriber A and learns that the subscriber at A desires to talk with the subscriber at B. The circuit including the sets at A and O is as follows: receiver 6 at station A1124L21-switch 54conductor 2conductor 55-switch 5EZ- receiver 56-switch 53conductor 57-1- switch 58--202318-7-812back to 6battery being supplied to this circuit from the source 35 over the conductors 3? and 40 and through the coils of the magnet of the relay K.

Assuming that the operator tests the line III and finds it idle, the switching device E is operated by inserting the plug P into the jack J,, the contacts of the plug and jack registering and making electrical contact in a manner similar to that described in connection with the plug P and jack J. A circuit will be completed through the magnets G, and L as follows: ground 60 winding 61 of G,,contact 62contact 6 conductor 64L,505l. G, becomes energized, disconnecting the line relay F and the line lamps X and at, from the line III in the same manner as described in connection with the line I. The magnet of L is energized opening the switch 28 and interrupting the first-described circuit of G and L which passed therethrough and closes a switch 66 in the circuit of the magnet H for a purpose to be described. The magnet of Z also opens a switch 49 in the circuit of the relay T previously described and causing the de'e'nergization of the relay T which results in the opening of the switches 52 and 53 and the disconnection of the operator from the cord. The magnet of L also closes a switch 67 in the circuit of the supervisory lamp N, which now becomes lighted over the following circuit: 515067conductor 68switch 69Nto ground at 70. The operator now signals the subscriber at B by depressing the ringing key S and connecting the ringing machine R in circuit with the signal 71 of the subscriber at B by closing the switches 72 and 73. Nhen the subscriber at B responds, the switch 7% will be closed and the relay K will be energized over the following circuit: 74cline conductor 75through the tip spring and tip contact of the switching device E-the conductor lthe conductor 76through the windings of the magnet of the relay K and the battery 77the conductor 7 8conductor 2-through the switching device E and the line conductor 78. The relay K opens the switch 69 and extinguishes the lamp N.

Upon the termination of the conversation, the subscribersretire, placing their receivers upon their hooks. As shown at A, the receiver 6 is placed upon the hook 7, which opens the hook switch 8, interrupting the circuit of the magnet K and causes the switches controlled thereby to assume the positions illustrated in the drawing. The circuit of the magnet of the relay X, will likewise be interrupted by the retirement of the subscriber at B, the switch 69 being closed, and causing the illumination of the lamp N. The retirement of the subscriber at A and the subsequent denergization of the magnet of the relay K causes the opening of the circuits of the magnets G and L at 42, so that they become deenergized, the magnet G releasing its contacts, so that they return to the position shown in the drawing and reconnect the line relay and line lamps of the line I to the line, thereby restoring the control thereof to the subscriber upon the line I. The switches 44-. and 45 in the circuit of the magnet H are also closed and the lamp U is lighted over the following circuit: 3l--ii5conductor 80lamp U. conductor 816750to 51, furnishing a signal to indicate to the operator that the subscriber at A has retired. It frequently happens that for some time the operator does not observe the disconnect signals, or is too busy to withdraw the plugs from the jacks, and in the meantime the subscriber at A desires another call, or a recall, as it is frequently spoken of. As explained, the line signalingapparatus of the line I has been restored to the subscriber at A who desiring a recall again removes the receiver 6 from the hook 7, thereby closing the switch Sand causing the actuations: of the '1 amps- X and a" as before.

In addition, a circuit is completed for the relay H, as-followsi 31 il5conductor 80 I*Iswitch 83'conductor 8lswitch 66-conductor 27contacts 22 and 4rconductor 26+-winding 87 of G'switch 16 battery 17to ground at 9. The magnet of the relay H is energized by current flowin over this circuit, interrupting the'strands '1 and 2 of the cord circuit C by opening the switchesfit and 58 and openingtheswitch S3 andclosing a switclrQO in the: locking circuit of the magnet H, whichis independ ent of 'the line circuit apparatus of the line I; This circuit is as'follows: 31-45- ground at 51. The continuity of the connectingdevice C beingnow interrupted, the

call may be answered by any operator with-- out interference. Assuming that another operator controlling-the cord C answers the call, theswitch D is closed by inserting the plug P into the ack y, whereupon the op =eration would be the same as described bemagnets L and G, as follows: 3130h L-2 910043 27 22'4l262 515 causing the energization thereof, the magnet of L breaking-the circuit of the relay H at 4.5. After this the operation will proceed as previously explained. Whenever the op erator takes down the connections by withdrawing the plugsP and P from the jacks in which they are employed, the circuit of the relay L will be opened and this relay 'deenergized, interrupting the circuit of the relay H, whereupon the apparatus will be restored to normal. I prefer to make the relay H slow operating and the relay L, fast releasing, to guard against incorrect operation.- This may be done in any of a number of well known ways.

It will also be obvious that the automatic disconnect will be operated should the subscriber at A initiate a call and that the operation will be the same as if-the subscriber at A had initiated a recall, except,

of course, it will now be controlled'by the hook switch at A instead of the hook switch'7.

It willbe appreciated: that one or'more of tails employed in illustrating the sameg' w'ith out departing from the spirit of-the in embodiment and" details-' having been illustrated for the-purpose of"- vention, such better describing the invention.

I cla1n1:

1. Ina telephone system, the combination of a telephone :lme,'a subscrlb'ers deviceat" a substation on said lme :by-the operation of which the subscribermay initiate a call or' a recall, telephone line interconnecting" mechanism, a switch for connectingsaid mechanism to saldtelephone line, means for operatively disconnecting said'mech anism from the line without disturbing" said switch and apparatus for causing" said means to operate to cause such disthe subscriber initiates a" connection when recall.

2. In a telephone system, the comb1nat1on of a telephone line, subscribers devices-at a substation on said line operated when a subscriber controlling the same initiates' calls and recalls,-telephone line interconnecting mechanism, a switch for connecting said mechanism to'said telephone line,a relay for operatively disconnecting said mechanism from the l line, without disturbing said switch and apparatus for causing said-relay to operate to cause such disconnection when the SUbSClllOQIlIHtlELtGS a recall.

3i In a telephonesystem, the combination" of a telephone line, subscribers (lGVlCQSZlUfii substation on sald lme operated when"a"sub-- scriber controlling the sameinitiates calls andrecalls, a cord 'circuit and aswitch' for" connecting said cord to said line, a relay for operatively disconnectmg said cord from the line, without disturbing the switch and apparatus for causing said relay to operate to cause such disconnection when the sub scriber initiates a recall.

4. In a telephone system, the combination of a telephone line, a substation on said line, 1

including a receiver hook switch controlled by the subscriber and by means of which calls and recalls are initiated, a cord circuit, a plug and jack switch for connecting said cord to said line, a relay for' severing the talking strands of the cordcircuit, without withdrawing the plug from the jack and apparatus for causingsald relay to operate to cause the interruption of the talking strands when the subscriber operates the hook switch to initiate a recall.=-

.5. In a telephone system, the combination of a telephone line, substation apparatus'on" said line, including a switch, a relay associated with the line controlled by said switch, a cord circuit, a second switch for connecting the cord'to the line, a disconnect relay for interrupting the talking strands of the cord circuit without operating the second switch and means including said first-named relay and said switch ior causing the actuation of said second-named relav when the subscriber initiates a recall.

6. In a telephone system, the combination of a telephone line, subscribers devices at a substation on said line controlled by the subscriber and operated when the subscriber retires or initiates calls and recalls, telephone line interconnecting mechanism, a switch for connecting said mechanism to said telephone liue,'mcans for operatively disconnecting said mechanism from the line without disturbing said switch, apparatus for conditioning said means for operation when the subscriber retires, and apparatus for causing the operation of said means to cause such disconnection when the subscriber initiates a recall.

7.'In a telephone system, the combination of a telephone line, a substation set on said line, including devices operated by the subscriber when the subscriber retires or initiates a call or a recall, telephone line in terconnecting mechanism adapted to be connected to said telephone line, means for operatively disconnecting said mechanism from the line, apparatus for conditioning said means for causing such disconnection when the subscriber retires and apparatus for causing said means to operate to cause such disconnection when the subscriber initiates a recall.

8. In a telephone system, the combination of a telephone line including a subscribers hook switch operated when the subscriber retires or when the subscriber initiates a call or a recall, a cord circuit and a switch for connecting the cord to the telephone line, a relay for interrupting the talking strands of the cord circuit, apparatus operated when the subscriber retires for conditioning said relay to operate to cause the interruption of such strands and apparatus operated when the subscriber initiates a recall to cause the actuation of said relay to cause the interruption of the talking strands.

9. In a telephone system, the combination of a telephone line, including contacts of a subscriber controlled switch operated by the subscriber when the subscriber retires, or when the subscriber initiates a call or a recall, a cord circuit, a switch for connecting the cord to the line, a relay adapted to interrupt the talking strands of the cord circuit, a circuit for said relay, apparatus operated when the subscriber retires to condition said circuit for completion and apparatus operated when the subscriber initiates a recall for completing the. circuit of said relay and causing the same to operate to interrupt the talking strands of the cord circuit.

10. In a telephone system, the combination of a telephone line, including a switch operated by the subscriber when the subscriber retires or when calls or recalls are initiated by the subscriber, a cut-off relay in the line circuit of the telephone line, a cord circuit, a circuit for said cut-ofl relay, closed during the conversational period, means controlled by the subscriber and operated when the subscriber retires for interruptingthe circuit of the cutofi relay, a disconnect relay for interrupting the talking strands of the cord circuit and means for causing the actuation of said disconnect relay to interrupt the talking strands of the cord circuit when the subscriber initiates a recall.

11. In a telephone system, the combination of a telephone line including-devices under the control of the subscriber and operated when the subscriber retires from the line or initiates a call or a recall, line signaling means associated with the line normally under the control of the subscriber, telephone line interconnecting mechanism adapted to be connected to the line, means operated when said mechanism is connected to the line for Withdrawing the control of the line signal apparatus from the subscriber and apparatus operated when the subscriber retires to restore the control of the line signal apparatus to the subscriber and apparatus for operatively disconnecting said mechanism from said line when the subscriber initiates a recall.

12. In a telephone system, the combination of a telephone line, including contacts of a subscribers switch, a line relay controlled by said subscribers switch, a cord circuit, a relay for interrupting the talking strands of the cord circuit and a circuit for said relay controlled by said line relay.

13. In a telephone system, the combination of a telephone line, substation apparatus on said line controlled by a subscriber, line circuit apparatus at the main station associated with said line, telephone line interconnecting mechanism, a switch for connecting said mechanism to said line, means for operatively disconnecting said mechanism from said line without disturbing said switch and devices in said line circuit apparatus controlled by the subscriber governing said means.

14. In a telephone system, the combination of a telephone line, substation apparatus on said line controlled by a subscriber, a main station, line circuit apparatus associated with the telephone line and locatedat the main station, telephone line interconnecting mechanism at the main station, a switch for connecting said mechanism to the line, means tor. operatively disconnecting said mecha- ;nism from said .line Without disturbing said .switch, means controlled by the subscriber for conditioning said first-named means for operation and devices in said line circuit apparatus controlled by the subscriber for causing the operation of said disconnect means.

15. In a telephone system, the combination 7 iota telephone line, including contacts of a receiver hook switch controlled'by the subscriber, a main station, line circuit apparatus including a linerelay controlled by the subscriber associated with the telephone line and locatedat the main station, a cord cir- .cuit, aplug and jackswitch for'connecting -the cord tothe telephone line, said cord includi'ngtalkingstrands, a relay for interrupting the talking strands without withidrawingcthe' plug fromthe jack, a circuit for said last named relay, a relay controlling said-circuit governed by the subscriber for conditioning said circuit for operation, and means including said line relay for com- ;pleting said circuit and causing said relay to operate to interrupt the talking-strandsof the cord circuit without disturbing said switch.

16. In a telephone system, the combination :'ofa telephone line including line conductors, a testing terminal and a cut-off relay associated'with the line and means including a winding-of said cut-0E relay independent of the-line conductors for placingan electrical potential on said testing terminal whenever theline is in use.

17. In a telephone system, the combination of a telephone line including line conductors,

substation telephone apparatus on the line, a testing terminal and a cut-ofl relay associated with the line and a circuit independent of the line conductors including a winding-of said cut-ofirelay for placing a potential on said-terminal whenever the substation apparatus is in use.

18. In a telephonevsystem, the combina tion of atelephone line including line conductors, substation apparatus in bridge "of said line, a testing terminal associated with the line, a line relay,a line signal and a cutoff'relay associated with said line and a cir- 'c-uit independent of the line conductors includingla winding of said cut-off relay for placing a'potential on said terminal when- Eever thesubstation bridge is closed.

19. Ina telephone-system, the combination of'a telephone line including line'conductors, a testing terminal and a cut-01f relayassociated with the line and meansineluding differential windings of said cut-oli relay independent of the line conductors for placing an electric potential on said testing terminal whenever the linelis in use.

-20.-In sav telephone system, the combination of:-

telephone line,'i: substation apparav tus on-: 'said. :l.in e, a v testing terminal I assoeaatedfi with saidiliea ariine eelay centrol led over said line, 4a cut-oii" relay controlling said line'relay and a circuit controlledby the line relay including a winding of the cut-0E relay for placing a potentialon said terminal when'said line is busy.

21. Ina telephone system, the combination of a telephone line, a substation onsaid line, a main station, a terminal for said line at said main station, line connecting mechanism at the main station, and switching means for connecting said mechanism to said line, a circuit for placing an electrical potential on said terminal whensaid line is busy, a'line relay controlled by theisubstation apparatus controlling said circuitya:

cut-ofi relay having a winding in saidcircuitand means controlled by saidswitching means for completing" a circuit through'said cut-off relay. V

22. In a telephone system, a cord clrcuit,

a line circuit and a second cord circuit, .a

switch to connectsaid first named cord cirvcuit to saidline circuit a sub-station 'connected-to said line circuit, electromagnetic apparatus in said cord circuit under the cont'rol of'said sub-stationapparatus, a disconnect signal controlled by said sub-station apparatus and associated with said first named cord circuit, a switch tosubsequently associate 'StlCl second named cord circu t telephone line'to' said mechanism to place said mechanism in conversational relation with a calling subscriber, means foroperatlvely disconnecting said mechanism from said line clrcultwlthout disturbing saidfi'rst named-means, and apparatus for causing said'means to operate to'cause said disconnection when a second callingsubscriber on the same line=initiates a call. 7

24. In a'telephonesystem,the combination of a'plurality of telephonelines, calling subscriber devices on said lines by which calls are initiated, telephoneiline interconnecting mechanism, means for connecting a telephone'linefto said mechanism to place said mechanism in conversational *relatlon with a calling subscrlbe'r, means for operativelydisconnecting said mechanism from said line without disturbing saidfirst named means and apparatus for causing said means to operate tocause said disconnection when a second oalhng.subscr1ber on-v the same line initiatesa call after the termination of the conversation initiated by the first 'calling subscriber. v

'25, v in a:teleplion'esystem, thecombina- 1 tion of first calling subscriber apparatus causing said means to operate to cause said and second calling subscriber apparatus, disconnection when a second calling sub- 10 telephone line interconnecting mechanism scriber on the same line initiates a call only and means for connecting said mechanism after the termination of a call participated With said calling subscribers, means for in by the first calling subscriber.

operatively disconnecting said mechanism In Witness whereof, I have hereunto from said subscribers Without disturbing signed my name this 20th day of July, 1915. 15 said first named means and apparatus for FRANK M. SLOUGH.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Iatents,

Washington, D. G. 

